Editing Vortec L31 cylinder head sources
- 19:48, 1 December 2012 Cobalt327 (Talk | contribs) deleted "Vortec L31 cylinder head sources" (Author request: content was: "==Overview== The Chevrolet L31 5.7L Vortec cylinder head is the best production head Chevy has made for the Gen I SBC engine to date. Because of this, it has become a very popular swap. These heads came with two different cas)